AusBonsai

good question.. possibly the tree itself, maybe a weaker gene in some more then others.. ie. a more fragile leaf?

I have had tridents for about 4 years and never encountered this problem...wind/heat burn yes but it hasn't looked like this, i have no suggestions of what it might be but thought i would try and add something to the discussion.

If I saw leaves like described/shown in this thread, and I discounted heat/sun/wind, I would be looking at infestation. did you dose them/it with confidor?

some infestations are not visable to the naked eye, and can be restricted to one tree....

I am not sure about the other guys but I have not used pestisides much in the past. I am learning this year and I gave a dose of eco-neem the other day when I noticed it was back if that is no good I will work through the other various chemicals such as confidor.
The only thing I can find for leaf curl in tridents is Verticillium wilt.

Problems
Diseases : Verticillium or Fusarium Wilt

Wilts may be contracted through infected seed, plant debris, or soil. This fungus begins and multiplies during the cool, moist season, becoming obvious when weather turns warm and dry. Plants wilt because the fungus damages their water conducting mechanisms. Overfertilization can worsen this problem. Able to overwinter in soil for many years, it is also carried and harbored in common weeds.
Prevention and Control: If possible, select resistant varieties. Keep nitrogen-heavy fertilizers to a minimum as well as over-irrigating as they encourage lush growth. Practice crop rotation and prune out or better yet remove infected plants.

Yet it just does not seem the same when you look further into it.
http://www.dpi.vic.gov.au/DPI/nreninf.n ... EF673?open
Any one want to guess a pest that would cause this damage. I have searched spider mite but that seems to be more of a discolouration than a deformed leaf.

maybe this?
http://www.na.fs.fed.us/spfo/pubs/fidls ... idl-ae.htm

I would rather it was something simple like this though
http://aces.nmsu.edu/CES/yard/2006/061706.html

I was reading somewhere in BT that japanese maple can sometimes show leaf burn due to root issues. They are related closely, so you may find something there?

I would definatly not rule out a root issue. The worst tree effected this year is one I only got late last season.
It seemed happy enough but I removed the excess soil above the roots and replaced with a little better stuff. Yet now I look back at the picture I can see the odd leaf that does show some signs of this but also you would not be silly for thinking it was just leaf burn. I have left the pic big if you want to zoom in.
I trimed back fairly hard to start working out a plan for the next year. Not the best front but I picked this picture because it shows a leaf that seems to be effected.(large pic again)
The regrowth after this last year showed definit signs of this problem wich looks alot like leaf burn but I was not too worried as it often comes and goes.
I trunk chopped bare rooted and put it in a grow box. The new growth is very badly effected at the moment. Obviously I need to work this out and put a stop to it.
What about the members that had issues with this last year how are they going?

I would also make sure there is no bugs in your soil munching on roots.
I did have a fig that was having leaf issues. After a talk at the club about pests and what too look for I decided to repot it and search through the root ball. Inside I found 3 little white grubs, and once removed the issue disappeared. Granted they are two different species and two different locations, but it may hold some relevance.
Have you bare rooted the tree this year?

I trunk chopped bare rooted and put it in a grow box

I thought you were a reader Aus
I do have those white grubs in my garden soil, but I have only found them in one or two pots after sitting them in the garden for extended periods. I did bare root this early spring and I am pretty sure that is not the problem. I have had leaf curl on trees in the yard as well that I have been growing out various species such as oak robina and tallow. I would get a spout of deformed leaves and then the leader would go back to normal growth again.
I got on the radio to ask Don Burke about it once thinking it was the white grubs he was adament that it was a leaf pest doing the damage that was too small to see or came out at night or something?
Maybe this tree has been pushed a little hard and the pest is giving it a good wallop?

Gimme a break, I got someone trying to give me a hard time, and I'm in putting data. only 597 more dog/cat breeds to go..


if you think the tree is being pushed too far, maybe leave it be this year, but heavy feed to to help gain strength. If it is a bug, it should help increase its resistance to it.
Seasol alot too should also help.

Not being either an entomologist or qualified horticulturist or a grower of many. In fact only one, now as the other went to the big bonsai garden after succumbing to poison from methyl bromide.
Which by the way manifest in much the same way as your tree;s. I have read with interest the theory's. So I thought I would add mine.
Mineral deficiency, I know this might be a bizzar sounding theory, but most fertilisers have some micro elements not all, also you are saying what about the other tree's.
I have noted when I fertilise some times the powder is lumpy so you might put too much or not enough.
Not enough won't hurt, too much might cause a salt build up as has been suggested.
Animal manure's are not a balanced fertiliser, fine on open ground not so in pot culture.

As I have said not being a grower of trident's I am likening to other tree's with similar faults. As you seem to have ruled out insect pests.
It is either as I have theorised a mineral deficiency or a fungal disease.
Just my two bob's worth. Pup

Hey Asus that sounds like good advice . I just had a chat with Ray on the phone and thats about what he suggested.
He said keep the water up don't let it dry out and also give it plenty of liqued feed to get it to grow through it.
He said the eco-neem insecticide that I used was fine but best bet is hit it with confidor and then use the pest oil on a regular basis for a while. So I will buy some confidor today.
I just gave it a dose of my best fertiliser and then humic acid. Seasol is a good idea I will give it some in a few days. It did get a seaweed fish emolsion fert less than a week ago so it should be heaps for now.

Got your reply after I posted Pup
It is tricky that much the same symptom can show from too much water as not enough and also too much of one mineral can cause a deficiency in another.
I have not written of the possibility of a pest or a virus but I hope and lean towards pest.
I believe the seaweed fish emulsion I did the other day is this trees first feed this season as it was repotted. I am very optimistic about the new range of liquid feed fertiliser I am using this year with plenty of trace elements and also the humic acid which I believe will free up and or balance any locked up nutrients.
This however does not rule out your theory as it would be running off what I gave it last year so far and I did not fertilise allot in Fall I hope to be better this fall.
So I will keep up all the goodies and use confidor and see what happens.

If you had the balls, you could try direct injecting fertilizer into the trunk of the tree.
It seems simple enough, but there was no information on what strength firt.